Telephone switch-board



(No Model.)

T. W. LANE.

TELEPHONE SWITGH BOARD.

wir [M+ Ha? Haw II l-llllllllrlll @M @D @D Q Q L--H--whL-l-M-w HHH-gf UNITED STATES PATENT OFFICE.

THOMAS W. LANE, OF BOSTON, ASSIGNOE TO HIMSELF AND CHARLES WILLIAMS, JR., OF SOMERVILLE, MASSACHUSETTS.

TELEPHONE SWITCH-BOARD.k

SPECIFICATION forming part of Letters Patent No. 244,625, dated July 19, 1881.

Application filed May 16, 1881. (No model.) h

To all whom @t may concern:

Beit known that I, THOMAS \V. LANE, of Boston, in the county of Suffolk and State of Massachusetts, haveinvented certain lm prove- 'ments in Telephone Switch-Boards, of which the following is a specification.

This invention relates to switch-boards having a series of parallel metallic strips, each connected to a dilferent line-circuit, a series of connecting-strips at right angles to the linecircuit strips, aud devices for connecting any two of the line-circuit strips through the medium of the connecting-strips.

The invention consists, as a whole, in a switch board embodying the following elements: First, a series of line-circuit strips, each adapted to be turned laterally to separate it from a ground-strip, against which it is normally held with a yielding pressure; sccondly, a series of connecting strips, each provided with as many plugs or connecting devices as there are line-circuit strips, said plugs being permanently secured to the connecting-strips and normally disconnected from the line-cir cuit strips, and adapted to make contact with the line-circuit strips, and at the same time to engage with and hold said strips from the ground-strip; and, thirdly, means for disengaging the line-circuit strips from the plugs of the connectin g-strips and permitting said plu gs and strips to automatically resume their normal positions. v

The object of the invention is to enable the connections between the line-circuit and counecting strips to be made and broken at a central office with the utmost facility, and to euable a single operator to attend to a greater p number of circuits than in switch boards of this class heretofore made in which a single f plug or connecting device, movable from one connecting strip to another, is employed for each line-circuit strip.

Of the accompanying drawings, forming part of this specification, Figure 1 represents a topplan view of a switch-board embodying my invention. Figs. 2 and 3 respectively represent sections on the lines .r a: and y y, Fig. 1.

The same letters relate to the same parts in all the figures.

In the drawings, B represents aswitch-board having a series of line-circuit strips, a, and a ground-strip, c, common to all Ithe line-circuit strips. The strips a are adapted to be moved so that they can lbe separated from the groundstrip, and are normally held in contact with said strip with a yielding pressure. In the present instance said adaptation is effected by pivoting the strips a at their ends on screws b, passing through the frame of the switch-board, and the yielding pressure is effected by springs s, attached to the strips and to pins secured in the frame.

The connecting strips d are, as usual, arranged at right angles to the line-circuit strips, and are insulated therefrom by the frame of the switch-board to which they are rigidly attached. Each strip clhas a series ofplugs or connecting devices, c, there being as many of said plugs in each strip d as there are line-circuit strips. These plugs are movable longitudinally toward and from the line-circuit strips, and are normally held away from said strips by springs f, but are adapted to be forced inwardly against the pressure of said springs to make contact with the line-circuit strips, as hereinafter described. Each plugchas a notch or recess, n, formed in the lower portion of its shank, and a shoulder or projection, l1', on the lower end of the plug, the under side of said shoulder being rounded off and adapted to come in contact with a line circuit strip, a, when the plug is forced inwardly through the orifice in the strip d, the pressure of the plug causing the strip a to be moved laterally or partially rotated upon its pivots, an d breakin g its cont-act with the groundstrip. inward movement ofthe plug c is sufficient to bring the shoulder 7L below the lower edge of the line-circuit strip the latter is caused by its spring to engage with said shoulder, as shown in Fig. 2, and the plug and strip are thus interlocked and .mutually held in contact with each other, so that neither can resume its normal position, the lineeircuit strip being dis connected from the ground-strip.

When the The general operation connectnig the line- IOO scriber, (say No. 1,) the plugs of any unoccupied connecting-strip corresponding to said line-circuit strips are pushed inwardly and engaged with the specified line-circuit strips, as already described, and as shown in Fig. 2, said strips being thereby disconnected from the ground-strip, as shown in Fig. 3, so that subscribers on the two circuits can coinmunicate.

I't is, of course, necessary to provide means for disengaging the plugs from the line-circuit strips, and allowing each to automatically resume its normal position. To this end I provide,in the present instance, a series of springretracted plugs or plungers, p, located on a strip, t', attached to the frame ot' the switchboard, and provided with rounded inner ends, without shoulders, adapted, when pressed against the line-circuit strips, to swing said strips' outwardly until they are disconnected from the shoulders of the plugs c, the latter being forced outwardly by their springs, and the line-circuit strips being brought by their springs into contact with the ground-strip as soon as the plugs p arc released by the operator. The outward movement of the plugs is limited by a pin, t, passing transversely throu gh theshank of the plug' below the strip d.

Itwill be seen that by the described improvements much time is saved in makin gand breaking connections as compared with a board in which a plug has to be moved from strip to strip, as heretofore, the operator being enabled to make and break the connections by a single rapid pressure on the sprin g-plu gs. An operator can therefore attend to a much larger number ot' circuits than has been possible heretofore.

Having thus described my invention, I claim- 1. In a switch-board of the class described, the combination of the line-circuit strips, each normally held in contact with a ground-strip, and adapted to be separated from thc latter, and the connecting-strips, each having as many spring-retracted plugs or connecting devices as there are line-circuit strips, said plugs being normallylisconnected from the line-circuit strips, and adapted to be engaged with and hold the latter when they are separated from the ground-strip, as set forth.

2. In a switch-board of the class described, the combination of aseries of line-circuit stri ps, pivoted at their ends, and held normally by springs against a ground-strip, a series ot' con necting-strips, each provided with as many spring-plugs or connecting devices e as there are line-circuit strips, each plug or connecting device being adapted by a single movement to separate from the ground-strip one of the linecircuit strips, to hold the latter so separated, and to connect it to the connecting-strip to which the plug belongs, anda series of releasing devices or plungers adapted to disengage the plugs c from the line-circuit strips and permiteach to resume its normal position, as set forth.

In testimony whereoi'l have signed my name to this specification in the presence of two subscribing witnesses.

THOMAS YV. LANE.

lVitnesses O. F. BROWN, Il. G. WADLIN. 

